The present invention relates to a method for producing a dental first attachment part for an implant in a jaw bone or for a second attachment part. Examples of a first attachment part which may be mentioned are a spacer, including individual spacers and temporary spacers, prosthetic constructions, tooth replacements in different forms, etc. According to the method, a model of the external shape of the first attachment part is scanned at a scanning station and the scanned information is digitized and transmitted in whole or in part on telecommunications and/or data link(s) to a production station. At the latter, a blank is machined in machining equipment so that the said external shape is applied to the blank. The invention also relates to a holder permitting application of a wax model of the external shape to a first attachment part, which can be of the said type. The first attachment part is connected or can be connected to an implant in the jaw bone or to a second attachment part. The holder also permits its application to a turntable so that the said external shape can be scanned by means of scanning equipment upon rotation of the table and holder.
It is already known to scan models of different types at scanning stations of dental technicians or dentists and to transmit a digitized version of the scan via a telecommunications and/or data link, for example the Internet, to a production station. It is also already known to apply the model to a holder which is rotated by means of a turntable during scanning. Reference may be made here to the PROCERA production system which is available on the market for products that are used in dentistry. In the said system, the blank is machined as a function of the digitized information received.
There is a need to be able to offer technically simple components allowing straightforward handling and manoeuvring in conjunction with the production of attachment parts of the type in question. The invention aims to solve this problem, among others.
There is a need to be able to offer a holder for different wax models which is easy and straightforward to use for the dental technician/dentist and with the aid of which the scanning function can be effected in a technically straightforward manner and so that it can be transmitted to a production station for production, from the blank, of a product having the external shape of the model. The invention solves this problem too.
In order to be able to transmit clear information with very great tolerance requirements in respect of the produced product (the attachment part), it is important, in the scanning principle which is based among other things on rotation of the scanned model, to be able to obtain an exact centring of the wax model and for the position of rotation or position of orientation of the model on the table to be coordinated or synchronizd with the position of rotation of the production unit for the rotatable blank which is to be milled. It should be noted here that accuracies of values around {fraction (2/100)}mm must be possible. The invention aims to solve this problem too.
It must also be possible for the model being used to be held exactly in the holder, and in this connection use is made of the realization that employing a range of inserts (or corresponding units) greatly simplifies the production of the contact surfaces in question. The attachment or securing of the respective selected insert is thus of crucial importance. The invention also solves the problems in these respects.
It is also important to be able to arrange the exchangeable inserts or units with respect to rotation and vertical setting. The invention solves this problem too.
The feature which can principally be regarded as characterizing a method according to the invention is that a unit which has the surface contact configuration of the implant or of the second attachment part, respectively, is selected from among a number of units with different surface contact configurations. The unit is applied in a holder which is centred on a turntable and is provided with or operates with angle-of-rotation information (information on the orientation of the holder on the table). A further feature is that the model is designed as a wax model which is applied on the holder over the unit with the selected surface contact configuration, after which the turntable is rotated and the external shape of the wax model is scanned. A further feature is that a blank with a pre-produced surface contact configuration which corresponds to the said selected surface contact configuration is machined in the machining equipment with the aid of the transmitted digitized information and the transmitted angle-of-rotation information (orientation information in the direction of rotation relative to the table).
In one embodiment, a blank is selected from among a number of blanks which have been pre-produced with different surface contact configurations, the said selected blank having a surface contact configuration which corresponds to the surface contact configuration of the unit in question.
A holder according to the invention can principally be regarded as being characterized in that it has bearing spaces for the unit or insert which can be selected from a number of units or inserts with different (possible) surface contact configurations for the implant or the abovementioned second attachment part. A further feature is that the wax model can be applied to the holder over the surface contact configuration on the selected unit or insert. For its centring and rotational orientation on the turntable, the holder is further provided with or cooperates with centring members or a function marking the angle of rotation.
In one embodiment, the holder has, on its underside, a recess for a centring pin incorporated in or forming the centring members which can be activated upon centring of the holder in the turntable. In a further embodiment, the holder is provided, on its underside, with one or more magnets for securing the holder to the turntable in a predetermined angle-of-rotation position which can be adjusted by means of one or more markings or indications arranged on the holder. The holder can be arranged in such a way that the respective unit or insert can be locked in a set selectable vertical position in association with the said bearing space. The wax model can be screwed to the unit by means of a screw which can be screwed in a thread in the unit or the insert. The said thread in this case corresponds with a thread arranged in the implant or in the second attachment part. The holder can also be arranged with a locking screw for the selected unit or insert. In addition, the centring pin can be adjustable, with respect to its position projecting from the holder, by means of a further locking screw. The angle of rotation of the respective unit or insert in the holder is preferably fixed in position in the holder.
By means of what has been proposed above, a holder is provided on whose upper side different inserts or units can be applied. The inserts represent different surface contact configurations which are used in the system. The respective wax model can be applied on the holder, and its external shape can be transmitted to the production station which uses blanks with corresponding prepared surface contact configurations, one of which is selected in each case. Known scanning principles which give a small amount of scanned information despite high accuracy requirements in respect of the product can be used. The dental technician or equivalent obtains an easy-to-manage holder function for wax models which can be applied to different types of spacers, including individual spacers and temporary spacers, different prosthesis components and implant systems and parts thereof. It is possible to easily adjust the height of the respective insert or unit in the holder. The bearing pin arrangement which is used can be adapted to different types of turntables.